HSK 6
偷偷
tōutōu副
stealthily; secretly; covertly; furtively
孩子偷偷把礼物放在桌下。
Hái zi tōu tōu bǎ lǐ wù fàng zài zhuō xià.
The child secretly placed the gift under the table.
Say it
Hold the button, say it, then let go.
Other HSK words sharing a character
Also free:
New in the HSK 3.0 word list at level 6.