'ow', 'ow', 'aw', 'au'

ACROSS

 4 I live in water and I rhyme with 'drawn'.

 5 Moo, moo.

 7 I start with p and contain the 'ou' sound. I am a unit of money.

 11 If you put me in your drink, you can sip through me.

 12 Hoot, hoot.

 13 I am a kind of fish. I contain the 'ou' sound. 

 15 I rhyme with 'scout'. I contain the 'ou' sound. I mean to yell loudly.

 16 I am the opposite to 'high'.

 17 Another word for 'sleep'. I contain the 'oo' sound and a 'z' in my word.

 18 Some people put tomato - - - - - on their food. I contain the 'au' sound.

 20 I am a black bird. I contain the 'ow' sound.

 21 If you're tired, this is what you do. I rhyme with 'sawn'.

DOWN

 1 I rhyme with 'hour'. You can buy me at the shop. I am white and powdery.

 2 You walk on me. I contain the 'ou' sound.

 3 I am another word for 'dress'. I contain the 'ow' sound.

 4 I use my index finger to - - - - -. I contain the 'oi' sound.

 6 I rhyme with 'low'. You wear me in your hair.

 7 I rhyme with cause, but I start with 'p'.

 8 I start with h and contain the 'ow' sound.

 9 Cats have - - - - - at the end of their paws.

 10 I rhyme with 'mouse'. You live in me.

 11 I look like 'stool', but end with 'p'. I contain the 'oo' sound.

 14 Too many - - - - - spoil the broth. I contain the 'oo' sound.

 19 I am worn by queens and kings. I contain the 'ow' sound.

 20 Babies do this before they walk. I contain the 'aw' sound.

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