diff --git a/.travis.yml b/.travis.yml
index 455f3c0e..45c29f60 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,6 +1,6 @@
 language: clojure
-lein: lein2
-script: lein2 midje :config .midje-grading-config.clj
+lein: lein
+script: lein midje :config .midje-grading-config.clj
 jdk:
   - openjdk7
 notifications:
diff --git a/src/structured_data.clj b/src/structured_data.clj
index ebfe1ce4..4a0fe0b3 100644
--- a/src/structured_data.clj
+++ b/src/structured_data.clj
@@ -1,16 +1,18 @@
 (ns structured-data)
 
 (defn do-a-thing [x]
-  :-)
+  (let [x2 (+ x x)]
+    (Math/pow x2 x2)))
 
 (defn spiff [v]
-  :-)
+  (+ (get v 0) (get v 2)))
 
 (defn cutify [v]
-  :-)
+  (conj v "<3"))
 
 (defn spiff-destructuring [v]
-  :-)
+  (let [[a b c] v]
+    (+ a c)))
 
 (defn point [x y]
   [x y])
@@ -19,96 +21,116 @@
   [bottom-left top-right])
 
 (defn width [rectangle]
-  :-)
+  (let [[[x1 y1] [x2 y2]] rectangle]
+    (- x2 x1)))
 
 (defn height [rectangle]
-  :-)
+  (let [[[x1 y1] [x2 y2]] rectangle]
+    (- y2 y1)))
 
 (defn square? [rectangle]
-  :-)
+  (= (width rectangle) (height rectangle)))
 
 (defn area [rectangle]
-  :-)
+  (* (width rectangle) (height rectangle)))
 
 (defn contains-point? [rectangle point]
-  :-)
+  (let [[[x1 y1] [x2 y2]] rectangle
+        [xp yp] point]
+    (and (<= x1 xp x2) (<= y1 yp y2))))
 
 (defn contains-rectangle? [outer inner]
-  :-)
+  (let [[bl tr] inner]
+    (and (contains-point? outer bl) (contains-point? outer tr))))
 
 (defn title-length [book]
-  :-)
+  (count (:title book)))
 
 (defn author-count [book]
-  :-)
+  (count (:authors book)))
 
 (defn multiple-authors? [book]
-  :-)
+  (< 1 (author-count book)))
 
 (defn add-author [book new-author]
-  :-)
+  (assoc book :authors (conj (:authors book) new-author)))
 
 (defn alive? [author]
-  :-)
+  (not (contains? author :death-year)))
 
 (defn element-lengths [collection]
-  :-)
+  (map count collection))
 
 (defn second-elements [collection]
-  :-)
+  (map second collection))
 
 (defn titles [books]
-  :-)
+  (map :title books))
 
 (defn monotonic? [a-seq]
-  :-)
+  (or (apply >= a-seq) (apply <= a-seq)))
 
 (defn stars [n]
-  :-)
+  (apply str (repeat n \*)))
 
 (defn toggle [a-set elem]
-  :-)
+  (if (contains? a-set elem)
+    (disj a-set elem)
+    (conj a-set elem)))
 
 (defn contains-duplicates? [a-seq]
-  :-)
+  (not (= (count a-seq) (count (set a-seq)))))
 
 (defn old-book->new-book [book]
-  :-)
+  (assoc book :authors (set (:authors book))))
 
 (defn has-author? [book author]
-  :-)
+  (contains? (:authors book) author))
 
 (defn authors [books]
-  :-)
+  (apply clojure.set/union (map :authors books)))
 
 (defn all-author-names [books]
-  :-)
+  (set (map :name (authors books))))
 
 (defn author->string [author]
-  :-)
+  (str (:name author)
+       (if (contains? author :birth-year)
+         (str " ("
+              (:birth-year author)
+              " - "
+              (:death-year author)
+              ")"))))
 
 (defn authors->string [authors]
-  :-)
+  (apply str (interpose ", " (map author->string authors))))
 
 (defn book->string [book]
-  :-)
+  (apply str (str (:title book)
+                  ", written by "
+                  (authors->string (:authors book)))))
 
 (defn books->string [books]
-  :-)
+  (str (cond
+         (empty? books) "No books"
+         (= (count books) 1) "1 book. "
+         (< 1 (count books)) (str (count books) " books. "))
+       (apply str (interpose ". " (map book->string books)))
+       "."))
 
 (defn books-by-author [author books]
-  :-)
+  (filter #(has-author? % author) books))
 
 (defn author-by-name [name authors]
-  :-)
+  (first (filter #(= (:name %) name) authors)))
 
 (defn living-authors [authors]
-  :-)
+  (filter alive? authors))
 
 (defn has-a-living-author? [book]
-  :-)
+  (not (empty? (living-authors (:authors book)))))
 
 (defn books-by-living-authors [books]
-  :-)
+  (filter has-a-living-author? books))
 
 ; %________%