sī 思 think

xīn

heart

sī-kǎo
思考

v.

think

sī-liàng
思量

v.

consider

sī-niàn
思念

n./v.

miss / longing

sī-xiǎng
思想

n.

thought; idea

sī-yì
思议

v.

to conceive; to understand (in negative use).

fā-rén-shēn-sī
发人深思
to arouse deep thought in people

dǔ-wù-sī-rén
睹物思人
seeing the things makes one think of sb.