她想了很久，最后只发出了一声'chu'，显然还是不确定。

She thought for a long time, then just made a '___chu' sound, clearly still unsure.

她在信的最后画了一个爱心，旁边写着‘chu’来表示亲吻。

She drew a heart at the end of the letter and wrote '___chu' next to it to represent a kiss.