【題目】My sister plenty of volunteer work in the past seven years.

【題目】My little cat can walk _______ his two hands for a long time.

【題目】My husband always ______ me flowers every week before we got married, but now he never ________.

【題目】Please don’t talk in class until you .

【題目】Don’t be ________, and please speak loudly.

【題目】It's dark, but my father hasn't come back, so my mother is (worry) about him.

【題目】— Do you like apples? — ________.

【題目】I find it difficult (work) out the math problem.

【題目】--Can he _________?

【題目】Although it takes energy (change) something into something else, it's better than (throw) things away.