Although it may look unpleasant, this condition is harmless and usually clears up with regular shampooing.

这可能不好看，但这种情况是无害的并且经常的洗头通常可以消除它。

Is there an extra charge for shampooing?

洗头要另外加钱吗?。

Rinse your hair thoroughly after shampooing it.

用洗发剂洗头后，要把头发冲洗干净。

Shall I trim a little before shampooing your hair?

洗头以前我帮你修一下头发好吗？

People with dry hair should also avoid daily shampooing.

干头发的人也应避免每天洗头。