让 — to ask / let someone do somethingHSK 2
让 + person + verb means to have or ask someone to do something: 她让我帮助她.
让 + person + verbHSK 2
让 means to have or tell someone to do something: 医生让我多休息.
把 + object + verb（the 把-construction）HSK 3
把 moves the object in front of the verb to stress what happens to it.
把 (the 把 construction)HSK 3
把 + object + verb moves the object in front of the verb to show what happens to it — common when handing something over: 把护照给他 (hand him the passport).
把 + object + verb + resultHSK 3
The 把 structure moves the object before the verb to show what is done to it, with a result after the verb.
把 + object + verb + complementHSK 3
The 把 sentence moves the object before the verb to show what you do to it; the verb needs a result or direction after it, e.g. 把门关好 'close the door properly'.
把……当成……HSK 4
"To treat/mistake A for B." 把 moves the object before the verb 当成 (to regard as): 我总是紧张地把油门当成刹车踩。
How to use this page
These 8 patterns all do the same job in Chinese, so they are worth seeing side by side — the differences between them are easier to feel when they are next to each other than when they are spread across six HSK levels. They range from HSK 2–6.
Grammar sticks through reading, not through lists. Each entry links to the reading it was taken from. Skim the page, then go read one of them and come back when a sentence stops making sense.