First, fill in.

1. Use (? ) as a unit is more appropriate; Use (? ) as a unit is more appropriate.

2. The oil painting stick is long (? ) centimeters.

3.2 meters = (? )cm？ 300 cm =(？ ) meter

30 cm -6 cm =(？ )cm 45 cm +20 cm =(？ ) cm

4. Sweet is 90 cm tall and relatively long (? ) cm, her height is 1 m.

Second, distinguish.

1. Which of the following figures is a line segment? Draw "√" below.

2. How many line segments are there in the picture below?

Fill in the appropriate length unit in the brackets.

4. Fill in ">" < or "=" in the box.

1 m 90 cm 2 m 200 cm？ 100 cm 1 m

20 cm 1 m -80 cm, 50 cm and 5 m? 1 m 80 cm 2 m

Fifth, do it.

1. Measure the length of the following line segments.

2. Draw a 5 cm long line segment.

Sixth, solve the problem.

1. Do you know how long an earthworm is?

2. There is a rope. Cut 30 centimeters, and there are 70 centimeters left. How long is this rope?

3. The bunny is going to grandma's house.

(1) Measure the length of each road below.

(1) Road length (? )cm； ② Road length (? ) centimeters.

(2) The rabbit walks (? ) No.1 road is near.

4. Small animals race.

(1) How many centimeters is the snail from the end?

(2) How many centimeters do ants climb more than insects?

Reference answer:

1. 1 .cm 2. 6 3 3.200 3 24 65 4. 10

Second, 1. (√) () (√) 2.5 1 10 8

Three, centimeters, centimeters, centimeters, centimeters, centimeters, meters, meters.

Fourth, > = = = <; & lt

Verb (abbreviation for verb) negligence

6. 1. 15cm+4cm = 19cm。

2.30cm+70cm = 1 00cm100cm =1m

3.( 1)①4 ②5 (2)①

4.( 1) 1 m-80cm = 20cm

(2) 90cm-70cm = 20cm