[ Grammar ]
You look tired. How long ……… (you / work) on your AI project?
A. have you worked
B. have you been working
C. are you working

Random Topics:
Grammar: AgreementFirst ConditionalModals for DeductionDefinite and Indefinite ArticlesQuantifiers & Modals of ObligationKinds of SentencesAdjective vs AdverbIdentify The TensesVerbs + Infinitives / GerundsComparative and Superlative AdjectiveOther quiz:
Many vs. Much › ViewHow ___times a day do you brush your teeth?
A. Much
B. Many
Pronounciation and Grammar › View
What do they often_________________ for lunch ?
A. to have
B. have
C. having
D. has
Grammar & Vocabulary › ViewJason: Did you _____ a good time last Saturday? Max: Yes, I ____!
A. have /didn’t
B. do/did
C. make/ did’t
D. have / did
Simple Past Tense › View
My sister ________ ___________ (not, clean) her room last week.
A. didn’t/clean
B. didn’t/cleaned
C. did/ cleaned
D. don’t/clean
