Why do you stand by and watch the milk __ over?A) boiling B)boiled C)from boiling D)having been boiledThe girl was often heard __ happily in her room .A) sing B)to sing C)singing D)sings

问题描述:

Why do you stand by and watch the milk __ over?
A) boiling B)boiled C)from boiling D)having been boiled
The girl was often heard __ happily in her room .
A) sing B)to sing C)singing D)sings