We are at your service. Don’t hesitate to _____us if you have any further problems.

My parents expected me to be the best. I don’t want to let them down.

Since several years ago, many supermarkets in China have _______ free plastic (塑料的) bags.

The artist is full of _________, so his painting is hard to understand.

to hospital in time, the patient infected withflu was saved at last.