in the following passage one word has been omitted in each line Write the missing word along with the word that comes before and after it the first one has been done for you as an example:--

1.)Schools offices are the hotbeds airborne_____
2.)diseases,which is the reason they are the
3.) first to shut down at the first threat of
4.)outbreak virus survives on hard surfaces
5.)as desks,keyboards,door knobs,even books.
6.) furniture therefore, must be cleaned regularly.