茫々(ぼうぼう)vast (ocean, desert, etc.), boundless, extensive, vague (e.g. memories), unclear, fuzzy, hazy, rampant (weeds, etc.), running wild, overgrown, unkempt (hair, beard, etc.), shaggy, scraggly

茫々(ぼうぼう)たる大(だい)海原(うなばら)を鯨(くじら)がゆったり泳(およ)いでいます。

A whale is leisurely swimming in the vast, boundless ocean. {vast (ocean, desert, etc.), boundless, extensive, vague (e.g. memories), unclear, fuzzy, hazy, rampant (weeds, etc.), running wild, overgrown, unkempt (hair, beard, etc.), shaggy, scraggly}

頭(あたま)を打(う)ったせいで色々(いろいろ)な記憶(きおく)が茫々(ぼうぼう)としている。

Due to hitting my head, various memories are hazy. {vast (ocean, desert, etc.), boundless, extensive, vague (e.g. memories), unclear, fuzzy, hazy, rampant (weeds, etc.), running wild, overgrown, unkempt (hair, beard, etc.), shaggy, scraggly}

茫々(ぼうぼう)とした白髪(はくはつ)を手入(てい)れするだけで見(み)た目(め)が若返(わかがえ)りました。

Just by grooming the unkempt white hair, the appearance became rejuvenated. {vast (ocean, desert, etc.), boundless, extensive, vague (e.g. memories), unclear, fuzzy, hazy, rampant (weeds, etc.), running wild, overgrown, unkempt (hair, beard, etc.), shaggy, scraggly}

廃校(はいこう)の校庭(こうてい)の茫々(ぼうぼう)たる草(くさ)むらを手入(てい)れするのに何(なん)時間(じかん)かかるだろうか？

How many hours would it take to maintain the overgrown, boundless grass field of the abandoned school? {vast (ocean, desert, etc.), boundless, extensive, vague (e.g. memories), unclear, fuzzy, hazy, rampant (weeds, etc.), running wild, overgrown, unkempt (hair, beard, etc.), shaggy, scraggly}

茫々(ぼうぼう)たるこの砂漠(さばく)で迷子(まいご)になろうものなら、あなたは生(い)きては帰(かえ)れないでしょう。

If you were to get lost in this vast desert, you probably wouldn't be able to return alive. {vast (ocean, desert, etc.), boundless, extensive, vague (e.g. memories), unclear, fuzzy, hazy, rampant (weeds, etc.), running wild, overgrown, unkempt (hair, beard, etc.), shaggy, scraggly}