Answer:
Scientists are creating vaccinations that prevent people from getting the bird flu. If the virus mutates, a new vaccine will need to be made. The vaccine needs to be tested, which can be dangerous. It will also take a long time for scientists to know whether the vaccine works or not.
Explanation:
The flu vaccine is injected under skin in a inactive form and the immune system responds with antibodies to the food protecting you from the future exposure to the flu. That's why sometimes you get the flu even though you got a shot because there's different forms of the flu.
The answer to your question is allocate because allocate is the opposite of the work appropriate :)
I am not sure how to explain this so i'll give you an example..
I <u>would have had</u> it done before homework
In this sentence, there are 2 words that represents past. "Would" and "Had", which makes up a past perfect.
