下列各句中，没有语病的一句是（ ）

Shall I help clean the kitchen, Mom?— Thank you. But you ________ it because I can do it myself. [ ]

We all know that, _____ , the situation will get worse[ ]

What were you doing yesterday afternoon— We were singing ____.

I’m sure I will get good marks in the finalexam.— I believe your parents will ______ your study ifyou try your best.