やってみよう: ___ a cinema on this street years ago. (There was / There were / There is) 答え: There was — 過去に1つの映画館があったので There was になります。"There were" は複数のものに使われ、"There is" は過去ではなく現在を表します。
There were = 2つ以上
過去に2つ以上のものが存在していたと言うときは、There were を使います。
There were two bakeries in the old town.
There were lots of people at the market.
There were many trees here before.
やってみよう: ___ two bakeries in the old town. (There were / There was / There are) 答え: There were — 2軒のパン屋 = 複数なので、There were を使います。"There was" は1つのものに使われ、"There are" は過去ではなく現在を表します。
1つ？ それとも複数？
まず数を数えましょう。1つのもの → There was（There was a cat.）。2つ以上 → There were（There were three cats.）。traffic, water, food, noise などの数えられない名詞も、複数ではなく1つのまとまりとして扱うため There was を使います。
There was a cat. (one)
There were three cats. (more than one)
There was a lot of traffic. (can't count → was)
Not "There were a lot of traffic." — say "There was a lot of traffic.". 交通量（traffic）は数えられない1つのまとまりなので was を使いますが、3匹の猫は複数なので were を使います。
やってみよう: ___ lots of people at the market last Saturday. (There were / There was / There be) 答え: There were — たくさんの人（Lots of people）= 複数なので、There were を使います。"people" は -s で終わっていませんが複数扱いになることを覚えておきましょう（There were lots of people）。
やってみよう: ___ a lot of traffic in the city centre. (There was / There were / There are) 答え: There was — 交通量（traffic）は数えられないので、1つのまとまりとして扱い、There were ではなく There was を使います。"There are" は過去ではなく現在を表します。
There wasn't = 1つ
1つのものが存在しなかったと言うときは、There wasn't（= there was not）を使います。
There wasn't a school here.
There wasn't a single car on the road.
There wasn't anyone at the door.
やってみよう: ___ a shop on this street back then. (There wasn't / There weren't / There no was) 答え: There wasn't — お店が1軒（A shop）なので、There wasn't を使います（複数のものに使う "There weren't" ではありません）。否定文でも1つか複数かのルールは同じで、1つなら wasn't になります。
There weren't = 2つ以上
2つ以上のものが存在しなかったと言うときは、There weren't（= there were not）を使います。
There weren't any cafés nearby.
There weren't many people at the park.
There weren't any buses after midnight.
やってみよう: ___ any cafés nearby back then. (There weren't / There wasn't / There no were) 答え: There weren't — Cafés は複数なので、There weren't を使います（単数に使う "There wasn't" ではありません）。否定文でも1つか複数かのルールは同じで、複数なら weren't になります。
Was there / Were there
質問するときは、was / were を文頭に置きます。1つのものには Was there...?、複数のものには Were there...? を使います。
Was there a park in your town?
Were there many shops?
Was there a lot of traffic?
やってみよう: ___ many shops in the old town? (Were there / There were / Was there) 答え: Were there — 質問するときは were が最初に来ます（Were there many shops?）。"There were" は説明する文であり、質問の形ではありません。また many shops は複数なので was ではなく were を使います。
やってみよう: ___ a market in the square, and ___ lots of stalls. (There was … there were / There were … there was / There was … there was) 答え: There was … there were — 1つの市場（One market）には there was、たくさんの屋台（Lots of stalls = 複数）には there were を使います。それぞれの名詞に合わせて、1つなら was、複数なら were を選びます。