in a way that is suitable for your purposes and needs and causes the least difficulty

They have conveniently provided a return envelope for you to use. 他们提供了一个回邮信封供使用，十分方便。

The box conveniently folds flat when not in use. 盒子在不使用时可以折叠起来，十分方便。

in a place that is near or easy to get to or use

The house is conveniently situated near the station and the shops. 这所房子靠近车站和商店，十分便利。

There is a cloakroom situated conveniently next to the front door. 前门旁边有一个衣帽间，很方便。

If you conveniently forget, lose, ignore etc. something, you do it because you think it will make life easier, or will avoid a problem.

humorous I asked her to clean up the kitchen but of course she conveniently forgot. 我让她打扫厨房，但她当然忘记了。

When it suits you, you conveniently ignore your own advice. 只要你愿意，你很容易就忽略了你给过自己的建议。