The conversation was mainly having to do with exchange of students between the two countries.

这时的话题主要是两国间交换留学生的问题。

youdao

Blues had enjoyed the better of the possession but were mainly having to play with it in their own half.

BBC: Cardiff Blues 27-9 Glasgow

The firm's problems come mainly from having bet all to build up a fixed-income business.

ECONOMIST: Peregrine Investments

Credibility, which was crucial in a strategy based mainly on influencing enemy psychology, meant having targeting options that were believable and proportional to any provocation.

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