Practice $1$

$\backslash$table$[[$Informal$,$Formal,Informal,Formal$],[$lack$,,$end,$],[$layout$,$stop,,$],[$sweat$,$shorten,,$],[$empty$,$get,,$],[$wrong$,$use,,$],[$cheap$,$need,,$],[$worse$,$next,,$],[$childish$,$mainly,,$],[$climb$,,$lively,$],[$show$,$say no$,,],[$tell$,$at first,,$],[$want$,$in the end,,$],[$seem$,,$cut down,$],[$go$,,$again and again,$],[$keep$,,$put off,$],[$live$,$carry out,,$]]$