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diff --git a/lessons/src/lesson027_multiple_subjects/code.gleam b/lessons/src/lesson027_multiple_subjects/code.gleam
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+++ b/lessons/src/lesson027_multiple_subjects/code.gleam
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+import gleam/io
+import gleam/int
+
+pub fn main() {
+  let x = int.random(2)
+  let y = int.random(2)
+  io.debug(x)
+  io.debug(y)
+
+  let result = case x, y {
+    0, 0 -> "Both are zero"
+    0, _ -> "First is zero"
+    _, 0 -> "Second is zero"
+    _, _ -> "Neither are zero"
+  }
+  io.debug(result)
+}
diff --git a/lessons/src/lesson027_multiple_subjects/text.html b/lessons/src/lesson027_multiple_subjects/text.html
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+<p>
+  Sometimes it is useful to pattern match on multiple values at the same time in
+  one case experession.
+</p>
+<p>
+  To do this you can give multiple subjects and multiple patterns, separated
+  commas.
+</p>
+<p>
+  When matching on multiple subjects there must be the same number of patterns
+  as there are subjects. Try removing one of the <code>_,</code> sub-patterns to
+  see the compile time error that is returned.
+</p>
diff --git a/lessons/src/lesson028_alternative_patterns/code.gleam b/lessons/src/lesson028_alternative_patterns/code.gleam
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+++ b/lessons/src/lesson028_alternative_patterns/code.gleam
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+import gleam/io
+import gleam/int
+
+pub fn main() {
+  let number = int.random(10)
+  io.debug(number)
+
+  let result = case number {
+    2 | 4 | 6 | 8 -> "This is an even number"
+    1 | 3 | 5 | 7 -> "This is an odd number"
+    _ -> "I'm not sure"
+  }
+  io.debug(result)
+}
diff --git a/lessons/src/lesson028_alternative_patterns/text.html b/lessons/src/lesson028_alternative_patterns/text.html
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+++ b/lessons/src/lesson028_alternative_patterns/text.html
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+<p>
+  Alternative patterns can be given for a case clause using the
+  <code>|</code> operator. If any of the patterns match then the clause matches.
+</p>
+<p>
+  When matching on multiple subjects there must be the same number of patterns
+  as there are subjects. Try removing one of the <code>_,</code> sub-patterns to
+  see the compile time error that is returned.
+</p>
+<p>
+  If a pattern defines a variable then all of the alternative patterns for that
+  clause must also define a variable with the same name and same type.
+</p>
+<p>
+  Currently it is not possible to have nested alternative patterns, so the
+  pattern <code>[1 | 2 | 3]</code> is not valid.
+</p>
diff --git a/lessons/src/lesson029_pattern_aliases/code.gleam b/lessons/src/lesson029_pattern_aliases/code.gleam
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+++ b/lessons/src/lesson029_pattern_aliases/code.gleam
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+import gleam/io
+
+pub fn main() {
+  io.debug(get_first_non_empty([[], [1, 2, 3], [4, 5]]))
+  io.debug(get_first_non_empty([[1, 2], [3, 4, 5], []]))
+  io.debug(get_first_non_empty([[], [], []]))
+}
+
+fn get_first_non_empty(lists: List(List(t))) -> List(t) {
+  case lists {
+    [[_, ..] as first, ..] -> first
+    [_, ..rest] -> get_first_non_empty(rest)
+    [] -> []
+  }
+}
diff --git a/lessons/src/lesson029_pattern_aliases/text.html b/lessons/src/lesson029_pattern_aliases/text.html
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+++ b/lessons/src/lesson029_pattern_aliases/text.html
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+<p>
+  The <code>as</code> operator can be used to assign sub patterns to variables.
+</p>
+<p>
+  For example, the pattern <code>[_, ..] as it</code> will match any non-empty
+  list and assign that list to the variable <code>it</code>.
+</p>