ripen|ripened|ripening

麦子即将成熟，等待收割。

The wheat is about to ___ripen, waiting to be harvested.

时机已经成熟，是时候实施我们的计划了。

The moment has ___ripened for us to carry out our plan.

番茄在阳光下会更快成熟。

The tomatoes are ___ripening faster in the sunlight.