Could I hang out with my friends—___. You have to prepare for your math test.

It’s the dialogue that is needed to ________ the understanding and trust between the two nations. [ ]

Encouraged by my science teacher, I set about my studies on developing my product, _____I hope I will succeed in applying for a patent（专利）.

下列句子中，没有语病的一项是（ ）

________does your father play table tennis —Twicea week.