「seem & appear」的差異在於描述主觀或客觀？
seem 和 appear 都有「好像；似乎」的意思，用法也很類似，甚至常可互換，不過語氣上， seem 多以「主觀感受」做推測，appear 則多根據眼前所見的「客觀事實」來描述。
因此同一個句子使用 seem 和 appear 時意思可說是相同的，不同之處僅在於說話者推測事情的主客觀程度。
以下句型用法：
➀ S + seem/appear + adj.
➁ S + seem/appear + to V
→It + seems /appears (+ that) + S + V…
The keys appear to be missing. I can't find them anywhere.
鑰匙似乎不見了，我到處都找不到它們。
→ 鑰匙不見為客觀事實的敘述，因此選用 appear 描述。
Jane seems upset about something. Her mood has been off all day.
珍似乎對某件事感到很沮喪，她一整天的心情都不太好。
→ 就客觀事實來說，我們無法確切得知 Jane 是否對某事感到沮喪，說話者主觀的推測占大部分，故使用 seem。
The rain seems/appears to be stopping, so maybe we can go out soon.
雨看起來好像快停了，我們或許等等就可以出門。
→「雨快停了」這件事可以是針對實際天氣狀況的闡述，也可以是個人的猜測，故 appear 和 seem 兩者皆可使用。
Frank seems to have come in late for work again today.
→ It seems (that) Frank has come in late for work again today.
法蘭克似乎今天上班又遲到了。
！！ seem 後面加 like + N 表示「像…」。（appear 沒有此句型）
Computers are getting really smart; they sometimes seem like real people.
電腦變得愈來愈聰明，有時候就像真人一樣。