diff --git a/.github/workflows/runtests.yml b/.github/workflows/runtests.yml
new file mode 100644
index 0000000..3c62d95
--- /dev/null
+++ b/.github/workflows/runtests.yml
@@ -0,0 +1,42 @@
+name: CI
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+    branches:
+      - master
+jobs:
+  test:
+    name: Julia ${{ matrix.version }} - ${{ matrix.os }} - ${{ matrix.arch }}
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        version:
+          - '1.3'
+          - '1.4'
+          - 'nightly'
+        os:
+          - ubuntu-latest
+          - macOS-latest
+          - windows-latest
+        arch:
+          - x64
+      fail-fast: false
+
+    steps:
+      - uses: actions/checkout@v2
+      - uses: julia-actions/setup-julia@v1
+        with:
+          version: ${{ matrix.version }}
+          arch: ${{ matrix.arch }}
+      - uses: julia-actions/julia-buildpkg@latest
+      - uses: julia-actions/julia-runtest@latest
+      - uses: julia-actions/julia-processcoverage@v1
+      - uses: codecov/codecov-action@v1
+        with:
+          file: ./lcov.info
+          flags: unittests
+          name: codecov-umbrella
+          fail_ci_if_error: false
+          token: ${{ secrets.CODECOV_TOKEN }}
diff --git a/src/Groups.jl b/src/Groups.jl
index 9dc67cb..4312ac2 100644
--- a/src/Groups.jl
+++ b/src/Groups.jl
@@ -7,7 +7,7 @@ import AbstractAlgebra: order, gens, matrix_repr
 
 import Base: length, ==, hash, show, convert, eltype, iterate
 import Base: inv, reduce, *, ^, power_by_squaring
-import Base: findfirst, findnext, replace
+import Base: findfirst, findnext, findlast, findprev, replace
 import Base: deepcopy_internal
 
 using LinearAlgebra
diff --git a/src/words.jl b/src/words.jl
index 9ef7383..1a1c76e 100644
--- a/src/words.jl
+++ b/src/words.jl
@@ -36,6 +36,8 @@ Base.@propagate_inbounds function Base.getindex(w::GWord, i::Integer)
     return first(syllables(w)[idx])
 end
 
+Base.@propagate_inbounds Base.getindex(w::GWord, itr) = [w[i] for i in itr]
+
 # no setindex! for syllable based words
 
 Base.convert(::Type{GW}, s::GSymbol) where GW <: GWord = GW(s)
diff --git a/test/FreeGroup-tests.jl b/test/FreeGroup-tests.jl
index bf7520a..fae5c6d 100644
--- a/test/FreeGroup-tests.jl
+++ b/test/FreeGroup-tests.jl
@@ -36,12 +36,14 @@ end
    @test isa(Vector{FreeGroupElem}([s,t]), Vector{FreeGroupElem})
    @test length(FreeGroupElem(s)) == 1
    @test length(FreeGroupElem(t)) == 2
-
+   @test Groups.FreeSymbol(:s, 1) != Groups.FreeSymbol(:s, 2)
+   @test Groups.FreeSymbol(:s, 1) != Groups.FreeSymbol(:t, 1)
 end
 
 @testset "FreeGroup" begin
    @test isa(FreeGroup(["s", "t"]), AbstractAlgebra.Group)
    G = FreeGroup(["s", "t"])
+   s, t = gens(G)
 
    @testset "elements constructors" begin
       @test isa(one(G), FreeGroupElem)
@@ -49,9 +51,23 @@ end
       @test length(G.gens) == 2
       @test eltype(gens(G)) == FreeGroupElem
       @test length(gens(G)) == 2
-   end
 
-   s, t = gens(G)
+      @test collect(s*t) == Groups.syllables(s*t)
+      tt, ss = Groups.FreeSymbol(:t), Groups.FreeSymbol(:s)
+      @test collect(t^2) == [tt, tt]
+      ttinv = Groups.FreeSymbol(:t, -1)
+      w = t^-2*s^3*t^2
+      @test collect(w) == [inv(tt), inv(tt), ss, ss, ss, tt, tt]
+      @test w[1] == inv(tt)
+      @test w[2] == inv(tt)
+      @test w[3] == ss
+      @test w[3:5] == [ss, ss, ss]
+      @test w[end] == tt
+
+      @test collect(ttinv) == [ttinv]
+
+      @test Groups.GroupWord([tt, inv(tt)]) isa FreeGroupElem
+   end
 
    @testset "internal arithmetic" begin
 
@@ -98,7 +114,7 @@ end
       @test o*p == one(parent(o*p))
       w = FreeGroupElem([o.symbols..., p.symbols...])
       w.parent = G
-      @test Groups.reduce!(w).symbols ==Vector{Groups.FreeSymbol}([])
+      @test Groups.syllables(Groups.reduce(w)) == Vector{Groups.FreeSymbol}([])
    end
 
    @testset "Group operations" begin
@@ -128,8 +144,14 @@ end
       c = s*t*s^-1*t^-1
       @test findfirst(s^-1*t^-1, c) == 3
       @test findnext(s^-1*t^-1, c*s^-1,3) == 3
-      @test findnext(s^-1*t^-1, c*s^-1*t^-1,4) == 5
+      @test findnext(s^-1*t^-1, c*s^-1*t^-1, 4) == 5
       @test findfirst(c, c*t) === nothing
+
+      @test findlast(s^-1*t^-1, c) == 3
+      @test findprev(s, s*t*s*t, 4) == 3
+      @test findprev(s*t, s*t*s*t, 2) == 1
+      @test findlast(t^2*s, c) === nothing
+
       w = s*t*s^-1
       subst = Dict{FreeGroupElem, FreeGroupElem}(w => s^1, s*t^-1 => t^4)
       @test Groups.replace(c, s*t=>one(G)) == s^-1*t^-1