be + chewing + sth
chewing 是 chew 的现在分词，与 be 动词构成进行时态。
The baby is chewing a toy.
宝宝正在嚼一个玩具。
咀嚼
chewings — plural of chewing
咀嚼某物的行为；咀嚼。；食用恰特草(的汁液)。；将散叶烟草置于脸颊附近咀嚼,以摄取烟草汁液。；[咀]嚼
the action of biting and grinding food in the mouth so that it becomes soft enough to swallow
咀嚼某物的行为；咀嚼。
The act by which something is chewed on; mastication.
食用恰特草(的汁液)。
The consumption of (the juice from) the khat plant.
将散叶烟草置于脸颊附近咀嚼,以摄取烟草汁液。
The consumption of loose leaf tobacco juice from tobacco plants by chewing leaves near the cheek.
Slow chewing helps you digest your food better.
细嚼慢咽有助于你更好地消化食物。
用法提示：chewing 作名词（动名词），表示“咀嚼”这个动作。
The doctor told him that his loud chewing at the dinner table was rude.
医生告诉他在餐桌上大声咀嚼很不礼貌。
用法提示：chewing 在此作名词，指“咀嚼”的行为。
She tried to focus on the taste of the apple instead of the sound of her own chewing.
她试着专注于苹果的味道，而不是自己咀嚼的声音。
用法提示：chewing 作名词，在介词 of 后表示“咀嚼”的动作。
chewing 是 chew 的现在分词，与 be 动词构成进行时态。
The baby is chewing a toy.
宝宝正在嚼一个玩具。
chewing 在此为名词，常与 of 连用，表示“对……的咀嚼”。
The chewing of food is the first step in digestion.
咀嚼食物是消化的第一步。
by + 动名词表示方式、手段；chewing 是动名词。
You can improve digestion by chewing slowly.
你可以通过细嚼慢咽来改善消化。
正式用语，多用于医学、生物学或学术语境；日常口语中用chewing更自然。
作名词表示一次咀嚼动作，常见于give something a chew等表达，语气较随意；该词更常用于动词。
非正式用语，强调咀嚼时发出声响或大口咬嚼，常用于吃零食等场景；可替换chewing但语体更生动活泼。
grammar · medium
易错句子I bought some chewing gums.
正确表达I bought some chewing gum.
chewing gum（口香糖）作为物质名词不可数，不能加-s表示多块；应说 a piece of chewing gum 或直接说 some chewing gum。
grammar · medium
易错句子I chewing my food slowly.
正确表达I am chewing my food slowly.
现在进行时结构是 be + 动词-ing，不能省略 be 动词，所以这里需要加 am。
grammar · medium
易错句子He is chewing the meat hardly.
正确表达He is chewing the meat hard.
hardly 意为“几乎不”，不能用来表示“用力地”；修饰动作“用力嚼”应使用副词 hard。
chewing（咀嚼）指用臼齿把食物磨碎以便吞咽；biting（咬）指用门齿咬住或咬下食物，不强调后续的咀嚼。
chewing（咀嚼）是中性词；munching（出声地嚼）带有出声、大口吃的随意感，常用 munch on + 食物。
chewing（咀嚼）的对象通常是放进嘴里的食物；gnawing（啃）多指用牙齿反复啃硬物（如骨头），不一定是为进食。
口香糖
She offered me a piece of chewing gum.
她递给我一块口香糖。
嚼烟
Chewing tobacco can harm your health.
嚼烟会危害你的健康。
充分咀嚼食物
Chewing food thoroughly helps you digest better.
充分咀嚼食物有助于你更好地消化。
张着嘴咀嚼
Chewing with your mouth open is bad manners.
张着嘴咀嚼是不礼貌的行为。
大声咀嚼
His noisy chewing irritated everyone at the table.
他大声咀嚼的声音惹恼了桌上的每个人。
chew (词根) + -ing (后缀)；无前缀。同根词：chewer (咀嚼者)、chewy (耐嚼的)、chewable (可咀嚼的)；同后缀词：eating (吃)、drinking (喝)
闲聊，闲扯
We spent the evening chewing the fat over a few beers.
我们晚上喝了几杯啤酒，闲聊了一晚。
深思，反复琢磨
He sat quietly, chewing the cud over the offer.
他静静地坐着，反复琢磨那个提议。
表演过火，夸张做作
The actor was accused of chewing the scenery in every scene.
这位演员被指责在每场戏中都表演过火。
Dictionary facts from ECDICT, WIKTIONARY.