尽管【jǐnguǎn】

尽管 before a verb invites someone to do it freely, with no need to ask or feel awkward. It's spoken, and almost always an offer to the listener.

A common frame is 有 + noun, then 尽管 + verb: "if there's anything, just…".

尽管放心 is a set reassurance, "rest assured".

Two 尽管

尽管 also means "although", and the two are told apart by where they stand. "Although" opens a clause, before the subject, and a second clause with 但是 or 还是 follows. "Feel free" sits after the subject, right before the verb, and the sentence can end there.

• × 尽管你问 → 你尽管问

Not with a negative

尽管 encourages an action, so it doesn't take 不 or 别. To tell someone not to worry, use 尽管放心 or 别担心, not both.

• × 你尽管别担心 → 你尽管放心