VHF is a short way of naming one group of radio waves. It comes from the first letters of Very High Frequency.

VHF這個字 is a short way of naming一種簡稱的方式 one group of radio waves用來指一組無線電波. It comes from它來自 the first letters of取 Very High Frequency這幾個字的字首。

Frequency means how fast the wave shakes each second, so VHF waves shake quite fast — faster than the AM radio band, but slower than the ones your phone uses.

Frequency means Frequency（頻率）指的是 how fast the wave shakes each second波每秒震動的快慢, so VHF waves所以 VHF 的波 shake quite fast震動得相當快 — faster than the AM radio band比 AM 廣播的波段快, but slower than the ones your phone uses但比你手機用的波慢。

What matters to a learner is what this group of waves is good for. VHF gives clear, clean sound with little hiss, so it is what FM music radio and old broadcast television used. It is also what ships, small planes, air traffic control, police and mountain rescue teams talk on, because the sound is easy to understand.

What matters to a learner對學習者來說重要的 is what this group of waves is good for是這組波能拿來做什麼. VHF gives clear, clean sound with little hiss VHF 給的是清晰乾淨、雜音少的聲音, so it is what所以 FM music radio and old broadcast television used FM 音樂廣播和以前的電視廣播用的就是它. It is also what它也是 ships, small planes, air traffic control, police and mountain rescue teams talk on船隻、小飛機、航管、警察和山難救援隊通話用的頻段, because the sound is easy to understand因為聲音容易聽懂。

Its weak point is distance: VHF waves travel mostly in a straight line, so hills and buildings block them, and they do not bend far round the earth. That is why FM radio fades when you drive into a tunnel or over a mountain, while AM keeps going.

Its weak point is它的弱點是 distance距離: VHF waves travel mostly in a straight line VHF 的波大部分走直線, so hills and buildings block them所以山丘和建築物會擋住它, and they do not bend far round the earth而且不太會沿著地球彎過去. That is why這就是為什麼 FM radio fades FM 廣播會變弱 when you drive into a tunnel or over a mountain當你開進隧道或翻過山頭時, while AM keeps going而 AM 卻還收得到。

You say the three letters one by one, V-H-F. It is used as a noun ("We heard them on VHF") and very often before another noun (a VHF radio, the VHF band, a VHF antenna).

You say你要 the three letters one by one一個字母一個字母唸, V-H-F V-H-F. It is used as a noun它可以當名詞用 ("We heard them on VHF"像『We heard them on VHF』) and very often before another noun也很常放在另一個名詞前面 (a VHF radio像 a VHF radio、the VHF band the VHF band、a VHF antenna a VHF antenna 這樣)。

It is a fairly technical word — you meet it in boats, aircraft, walkie-talkies and radio equipment, not in ordinary conversation.

It is它是 a fairly technical word一個相當技術性的字 — you meet it你會 in boats, aircraft, walkie-talkies and radio equipment在船、飛機、對講機和無線電設備裡遇到它, not in ordinary conversation而不是在日常對話裡。

Note that the dictionary line "waves that move very quickly" is about the shaking of the wave, not about speed of travel; all radio waves travel at the speed of light.

Note that請注意 the dictionary line "waves that move very quickly"字典裡『waves that move very quickly』這句話 is about是在講 the shaking of the wave波的震動, not about speed of travel而不是傳播的速度；all radio waves travel所有無線電波的傳播速度 at the speed of light都是光速。