reírse
You say, "Me hiciste reír." Lit.: "Me you made to laugh."
Tengo que reír
Solo me duele cuando reír.
Gee, I just had to laugh a little at this one. :) The Spanish word for that is 'Mamá caliente'.
You can say "Vivir, reír, amar, mi amigo"
Mi trabajo es hacerte reír.
Tiene una risa escalofriante -Adam NK
reir a carcajadas
to laugh = reír
lol means laugh out loud. To say laugh out loud in Spanish you say, "laugh in high voice" or, "reír [e]n voz alta." or rva. In acronyms such as these, prepositions (to, of, on, in, by) are frequently omitted. There is a site called que chistoso rva (how funny lol) on YouTube.
Por que ries? (accent on 'e' in 'que') - question porque ries (no accent) - statement