Straight pants: the thighs are as thick as the calves, which are relatively loose and suitable for people who are too thin. Not recommended.
Tight pants: also known as tight pants or pencil pants, suitable for very thin people. They will be tighter than tights. If you like this tight effect, you can wear tight pants.
In fact, you can try slim pants and close-fitting pants, but relatively close-fitting pants are more suitable for thin people. Are you taller or better to wear slim pants?