下列各句中，没有语病的一句是（ ）

Hannah was busy with work then but she still tried her best to some time from her tight schedule to visit her mother.

It is ______ of you to call on your aunt from time to time.

I tried many times, but I still failed in the experiment. –Don’t be discouraged. _______ and the problem will be settled.

Will you see to________ that you will take good care of my car while using it