23b. Choose the correct answer.
1. ... foxes and bears are omnivores because they eat animals and plants.
a. Neither
b. None
c. Both
2. There are a frog, snake and hawk ... of them can be a herbivore
a. neither
b. either
c. none
3. Tertiary consumers feed on .. of primary and secondary consumers.
a. none
b. neither
c. either
4. Do... of you have any Biology book I can borrow?
a. neither
b. both
c. either
5. 'Why didn't you go for the Biology field trip last weekend?' 'Because ... of my classmates
was invited
a. both
b. none
c. either
6. Bill and I have been ... very tired because we have been doing experiments on
photosynthesis since this morning.
a. all
b. both
c. none