Whenever you want to imply that something is "meh", you can use "还"(hái).

Structure:
As well as continuation,"还"(hái) can also be used to weaken positive adjectives. This is similar to saying "quite" or "reasonably" in English.

Examples:

Wǒ hái hǎo.
我 还 好。
I'm OK.

Nà ɡè yuèduì hái kéyǐ.
那 个 乐队 还 可以。
This band is so-so.