Join over 19,000 others and become a member of - it's free!

join for free

This site is written by

victoria Williams Music Theory

Victoria Williams

LmusTCL BA Mus (Hons) MISM

Learn more...

book cover notes


We have 3743 guests and 4 members online

Please note: this website is not run by the ABRSM and is a completely independent business.

Get the MyMusicTheory Course Book

Browse by Music Grade: Grade 1 | Grade 2 | Grade 3 | Grade 4 | Grade 5 | Grade 6 | Grade 7 | Grade 8 | DiplomasWhat Grade am I?

bs3Download this Grade 3 Music Theory Course or buy the Printed Book Version

Buy Grade 3 Theory Past Papers

Get some help!

7. Adding Bar Lines & Time Signatures

Grade Three Music Theory - Lesson 7: Adding Bar Lines or a Time Signature to a Melody (UK Version)

Suitable for:  ABRSM Grade 3   Trinity Grade 3   GCSE   AP Music Theory Beginners 

New at Grade Three

In your grade three music theory exam you might have to add a time signature to a short melody.

Although you also had this task at grade two, it’s a bit harder at grade three.

This is partly because the time signatures 3/4 and 6/8 have the same number of quavers in them, so it’s harder to tell them apart.

You’ll also find the rhythms are a bit more complicated, which might include demisemiquavers, dotted notes and tied notes.

The time signatures you need to choose from at grade three are:

  • 2/2, 3/2 (minim beat)
  • 4/2 (minim beat, ABRSM only)
  • 2/4, 3/4, 4/4 (crotchet beat)
  • 3/8 (quaver beat)
  • 6/8, 9/8, 12/8 (dotted crotchet beat – these are the compound time signatures)

Adding a Time Signature

To work out a time signature you need to discover two things:

  1. What kind of beat is the main beat?
  2. How many of these main beats are there per bar?


The easiest way to work out what kind of beat is the main beat, is to look for notes which are beamed together. (Obviously you need to look for a bar with quavers or semiquavers).

  • Notes are beamed to add up to one whole beat. You need to work out what kind of note you need one of, to equal the notes which are beamed.
  • When a new beat begins, a new beam begins too.
  • Notes can also be beamed to add up to one whole bar, but only in simple time.


To work out how many main beats per bar there are, draw a circle around each group of notes that makes one full beat. Each circle has to contain the same value of notes overall. Then count the number of groups you circled. The number of circles in one bar is the number of beats per bar.


To work out the time signature, look at the information you have worked out.

The number of circles per bar will be 2, 3 or 4. This tells you whether the time signature is duple, triple or quadruple. Duple time signatures have either 2 or 6 as their top number. Triple time signatures have 3 or 9 as their top number. Quadruple time signatures have 4 or 12 as their top number.

If each circle adds up to the value of a minim, the beat is a minim and the time signature will have a lower number 2. The top number will be 2, 3 or 4.

If each circle adds up to a crotchet, the lower number will be 4. The top number will be 2, 3 or 4.

If each circle adds up to a quaver, the lower number will be 8. The top number will be 3. (2/8 and 4/8 don't come up in the grade 3 exam).

If each circle adds up to a dotted crotchet, the lower number will be 8 (compound time). The top number will be 6, 9 or 12.


Here’s an example question.

Add the time signature to this melody:

add the time signature to this melody

Look at the first bar and notice how the semiquavers are beamed. There are two joined together, and four joined together. Use the larger group.

Four semiquavers=1 crotchet. The first note of that group (the first G) must be the start of a new main beat, so the main beat is a crotchet. (If the main beat had been a dotted crotchet, the other two semiquavers would also be joined on, making six beamed semiquavers in total).

Look at bar 3. The quavers and semiquavers are again grouped together to add up to one crotchet each.

The main beat is therefore a crotchet beat. 


Next, work out how many crotchets there are in each bar:

divide each bar up

In each bar there are 3 crotchets' worth of beats.
(Notice that the last bar doesn’t have a bar line at the end – it’s not a complete bar, so it doesn’t matter how many beats there are in it.)

Because the main beat is a crotchet, the lower number of the time signature is 4. Because there are three crotchets per bar, the top number is 3. The time signature is 3/4.


Here is another example:

a more difficult example

Choose bar 4 to look at first, as it has the most quavers/semiquavers.

  • Remember that the notes are beamed to together to make one of something. What value do the beamed notes add up to? The answer is: the dotted crotchet. One dotted crotchet is worth the same as [semiquaver+dotted quaver+ quaver], and one dotted crotchet is worth the same as three quavers.
  • It is compound duple time, because the main beat is a dotted note. The top number is 6.
  • The bottom number is 8. (The bottom number is 8 because there the top number is 6, and there are 6 quavers' worth in each bar.)


(ABRSM only) Sometimes there will be no quavers or semiquavers to help you. If that is the case, you need to remember that there can only be 2, 3 or 4 beats per bar, no other number! (For grade 3 theory, that is!) Look at this example:


another example

  • The first bar contains eight crotchets.
  • Crotchets can’t be the main beat, because there are too many of them (8).
  • Semibreves can't be the main beat, because semibreves are never used as the main beat (there are no time signatures with the lower number 1).
  • So, minims are the main beat.
  • There are four minims per bar.
  • The time signature is 4/2.


Adding Bar Lines

You might be asked to add bar lines to a melody.

Look carefully at the time signature and write down the following information:

  • How many beats
  • Type of beats

Take your time – it’s easy to make mistakes when you’re in a rush!

Carefully count the notes, marking off each complete beat.

When you’ve reached the number of beats you need to make a complete bar, use your ruler and draw a neat bar line quite close to the first note of the next bar. Continue until you get to the end of the piece.


Pay very careful attention to the end of the piece.

  • If there is a bar line after the last note, the last bar must be complete.
  • If there isn’t a bar line, the last bar can contain any number of notes, (as long as it’s not longer than a normal bar!) It might or might not be complete, so be careful.


Here’s an example:

add bar lines to this melody

The time signature is 4/4, so each bar needs four crotchet beats.


Count and mark off the crotchet beats until you reach four, then draw a bar line:

count and mark off the crotchet beats



repeat in the next bar


Double check the last bar – there is a bar line here so it should be a complete bar:

double check the last bar



now on amazon topbanner normalamazon logo