String Concatenation

Name:

Date:

Class:

Quick Questions

Shade in the A or B circle for each question.

1. Does + join two strings together in JavaScript?

A Yes

B No

2. Is - used to join two strings together?

A Yes

B No

3. Does leaving out + between two strings cause an error?

A Yes

B No

4. Can you concatenate a string literal with a variable?

A No

B Yes

5. Is a + + b valid syntax for joining two strings?

A No

B Yes

Match the Pairs

Draw a line connecting each item on the left to its match on the right.

Left column		Right column
1"Hi " + name		AWrong - concatenation uses +, not -
2first + " " + last		BJoins first, a space, and last into one string
3Combines two strings into one using +		Cgreeting + "!"
4Joins a string literal with a variable's value		D"Age: " + age
5let msg = "Hi " - name;		EWrong - only one + is needed to join two values
6let z = x + + y;		FJoins the string "Hi " with the value of name

Definitions

Fill in the Blanks

Complete each line of code by filling in the missing parts.

let msg = "Hi " _ name;

let full = firstName _ lastName;

let years = "Age: " _ age;

let combo = a _ b + c;

let msg2 = greeting _ "!";

Spot the Error

Shade in the letter of the line that contains an error.

Question 1

A let msg = "Hi " - name;

B console.log(msg);

C let x = 1;

Question 2

A let a = "Hello";

B let b = a "World";

C console.log(b);

Question 3

A let x = "A";

B let y = "B";

C let z = x + + y;

Question 4

A let first = "Sam";

B let last = "Lee";

C let full = first + last;

D let full2 = first * last;

Question 5

A let name = "Amy";

B let msg = "Hi " + name;

C console.log(msg);

D let x = 1;

E let bad = Hi + name;

Answer Key

String Concatenation

Section A: Quick Questions

A — Yes

B — No

A — Yes

B — Yes

A — No

Section B: Match the Pairs

"Hi " + name → Joins the string "Hi " with the value of name

first + " " + last → Joins first, a space, and last into one string

Combines two strings into one using + → greeting + "!"

Joins a string literal with a variable's value → "Age: " + age

let msg = "Hi " - name; → Wrong - concatenation uses +, not -

let z = x + + y; → Wrong - only one + is needed to join two values

Section C: Definitions

+ — Joins two strings together into one when used between them.

Section D: Fill in the Blanks

let msg = "Hi " + name;

let full = firstName + lastName;

let years = "Age: " + age;

let combo = a + b + c;

let msg2 = greeting + "!";

Section E: Spot the Error

A — Concatenation uses +, not -, to join strings.

B — Missing + between the two strings being joined.

C — Extra + causes invalid syntax - only one + is needed.

D — Concatenation uses +, not *, to join strings.

E — The string "Hi " needs quotes, or Hi is read as a variable.