=1

你

nǐ

you (informal, as opposed to courteous 您 nín)

=1

你

nǐ

you (Note: In Taiwan, 妳 is used to address females, but in mainland China, it is not commonly used. Instead, 你 is used to address both males and females.)

=2

星期二

Xīngqīèr

Tuesday

=2

星期二

xīngqī'èr

Tuesday

3

有空

yǒukòng

to have time (to do sth)

=4

嗎

má

(coll.) what?

=4

嗎

mǎ

used in 吗啡 mǎfēi

=4

嗎

ma

(question particle for "yes-no" questions)