canker|cankers

嘴唇上的口腔溃疡可能非常疼痛。

___Canker ___sores on the lips can be very painful.

这些玫瑰得了溃疡病，导致它们的茎干上出现了坏死的斑块。

The roses developed ___cankers, causing dead patches to appear on their stems.

嫉妒是一种会逐渐侵蚀友谊的毒瘤。

Jealousy is a ___canker that slowly destroys friendships.