Are these 3 sentences correct Many thanks in advance
He tends to get nervous while I am changing his nappies
He tends to get cranky while I washing him
He tends to get annoyed while I am changing his clothes

Question

Are these 3 sentences correct Many thanks in advance
He tends to get nervous while I am changing his nappies
He tends to get cranky  while I washing him 
He tends to get annoyed  while I am changing his clothes

Answer

Apart from the missing 'am' in sentence two, they're grammatically correct.

Just a few comments:

'When' would be a better connector than 'while' in all of these sentences e.g. "He tends to get annoyed when I am changing his clothes."

Do you really mean 'nervous'? I can't see why a baby would be nervous when having his nappy changed.The adjective 'nervous' means apprehensive, as if he were afraid of what was going to happen next. This is a common 'false friend' across European languages, and many non-native speakers of English mistranslate 'agitated' or 'upset' as 'nervous'. Do you mean agitated or upset, perhaps?

"He tends to get upset when I'm changing his nappy.'

And note that we usually use the singular word 'nappy' in this context.

Answer

Sentence two needs an extra word - I'm sure you can spot it.

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