[ Grammar ]
While scientists know a lot about ______________hardy lizards, the one mystery that has never been completely solved is how they keep hydrated.
A. these
B. this

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Grammar › ViewWhich word in this sentence is a noun?
The brown mouse is running fast.
A. mouse
B. brown
C. running
D. fast
Grammar › View
Identify the complement type. The teacher assigned the students extra homework.
A. Direct Object
B. Indirect Object
C. Predicate Adjective