a lot of young men smoke weed, Cannabis, also known as marijuana
Yes, marijuana use is defintely on the rise. My whole ocutry just legalized it, effective in October. 
really, it  can be used by smoking, vaporizing, within food, or as an extract.
I went to a legal weed store in California and you could buy leaves, drinks, chocolate, cigarettes- everything marijuana. 
really, i learnt the effects is within minutes when smoked, and about 30 to 60 minutes when cooked and eaten.
It's hard to get the dose right when you eat or drink marijunana. 
yes, you are right and its effects on the long term may include addiction, decreased mental ability in those who started as teenagers, and behavioral problems in children whose mothers used cannabis during pregnancy.
It definitely has good and bad effects on people. It can also help with pain relief. 
yes you are right,  Cannabis is mostly used recreationally or as a medicinal drug, although it may also be used for religious or spiritual purposes.
I'm glad it's legal in Canada. It's no more dangerous than alcohol, in my opinion.