To exaggerate a small problem and make it seem much bigger than it really is.
преувеличивать маленькую проблему и делать ее гораздо более значимой, чем она есть на самом деле. (preuvelichivat' malen'kuyu problemy i delat' yeye gorazdo bolee znachimoy, chem ona yest' na samom dele)
"She made such a big deal out of forgetting her phone; she really made a mountain out of a molehill."
"Она так раздула проблему, что забыла свой телефон; она действительно сделала гору из кучи." (ona tak razdula problemyu, chto zabula svoy telefon; ona deystvitel'no sdela goryu iz kuchi)
you shouldn't form an opinion on someone or something based...
The more people there are, the better the situation becomes.
to make a silly or careless mistake
to boost someone’s confidence or enthusiasm
feeling very worried or tense because of problems
To be less advanced or slow compared to competitors.