我考虑了很久，终于找到了一些理由。

I considered for a long time, finding out some reasons finally.

youdao

我考虑了很久，最后还是买下了这个发夹。

I thought for a long time, finally bought this hairpin.

youdao

我考虑了很久，确信现在是改变的时候了。

Ive thought about this for a long time, and I'm confident that it's time for a change.

youdao

And I thought about it. I thought about it a lot.

我考虑了很久，仔细思量了。

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I've been thinking about this for a long time.

我已经考虑了很久了。

I'm ready to 实战 - SpeakingMax英语口语达人