In imperative BA sentences, however, the particle LE may sometimes be used with result complements simply to soften the tone. For example,
请把东西放好!
qǐng bǎ dōng xī fàng hǎo !
Please put your things in order.
Whereas
请把东西放好了!
qǐng bǎ dōng xī fàng hǎo le !
has a condescending or persuasive tone and might be used by a mother to a child or a teacher to a pupil.
LE is not generally used in imperatives with complements of other types (e.g. direction, location, etc.). One says:
请大家把作业交上来!
qǐng dà jiā bǎ zuò yè jiāo shàng lái !
Please all hand in your homework. / Would you all please hand in your homework.
请大家把证件拿出来!
qǐng dà jiā bǎ zhèng jiàn ná chū lái !
Please take out your personal documents. / Would everyone please get out their personal papers.
请把垃圾倒在这儿!
qǐng bǎ lā jī dǎo zài zhè ér !
Please tip your rubbish/litter here.
But not usually:
*请把垃圾倒在这儿了!
*qǐng bǎ lā jī dǎo zài zhè ér le !
However, LE and D ZHE may sometimes be used as complements themselves in imperatives to indicate completion or continuation of the verb in question:
请把蛋糕吃了。
qǐng bǎ dàn gāo chī le 。
Please finish the cake.
请把我的大衣拿着。
qǐng bǎ wǒ de dà yī ná zhe 。
Please hold my coat.
[1] Yip, P. C., Rimmington, D., Xiaoming, Z., & Henson, R. (2009). Basic Chinese: a grammar and workbook. Taylor & Francis.