[ Grammar for TOEFL ]
The director was uncertain __ the team would be able to complete the project before the deadline, considering the unexpected challenges they faced during the development phase.*
A. why the team was so determined to push forward,
B. because the team was known for its efficiency,
C. whether
D. although they had managed to overcome similar issues in the past,
overcome similar issues in the past,

Random Topics:
Conditional Sentences and AdverbsPreposition of DirectionDefinite ArticlesAdjectives and PrepositionsPhrasesCoordinating and Subordinating ConjunctionsWH Questions and Simple Past TenseDistinguishing Future TensesHomophone & HomonymPresent PerfectOther quiz:
Tenses › ViewThey … for an hour before the doctor came.
- had been waiting
- waited
Vocabulary › View
The biggest ___________ I face to going to college in Canada is money. It is so expensive.
A. barrier
B. fit in
C. empathy
D. courage
Preposition on Time › ViewI always visit my grandpa ___ Sunday night.
A. at
B. on
C. in
D. X
The -ing Form of Verbs › View
I learned English by _____ to English friends.
A. speak
B. speaking
C. spoke
D. are speaking
