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.
"Him" is the indirect object.
"Lena" is the subject, the person performing the action. "Tell" is the verb, the action performed. "The truth" is the direct object, the recipient of the action. "Him" is affected by the action.
Hope this helps! :)
Sergei's reaction is hostile. He is not interested in answering
