Have they tried to send information to us?不定式 tried to 在这里做什

Have they tried to send information to us?不定式 tried to 在这里做什 They tried to keep this____happening. They tried to have her talking all the time.But it was no us I have just tried to ring you... They tried their best to do __________ help us. A. that they they tried to set the Embassy on fire. they tried to ___ They have tried to limit such imports in order to protect th They have tried ___ to persuade him to give up smoking. they have always tried hard to.请解释一下这个句子的语法,为什么always在have的后 They tried to fool you into coming after us翻译这句话 they have been trapped for seventeen hours. they tried to co They have been trapped for sevevteen hours.They tried to com