He was inviting me on his yacht.

他来邀请我乘他游艇出海。

If you want to arrive secretly in a country, arriving in a populous harbor by yacht is not the way to do it.

如果你想到达个国， 乘游艇到达人口稠密的海港并是办法。

He has the yacht, and the captains just sit there by the phone every day just in case he wants to go out on it.

他有艘游艇，船长每天都坐在电话旁，以防他想乘游艇出去。